Field of the Invention
The present disclosure relates to a light conversion plate, and a light-emitting diode package, a backlight unit, and a display device which include the light conversion plate, and more particularly, to a light conversion plate which can be used in a light-emitting diode package to obtain high brightness and high color reproducibility, and a light-emitting diode package, a backlight unit, and a display device, in which the light conversion plate is used.
Discussion of the Related Art
A light-emitting diode (LED) is a semiconductor device which converts electricity into light by using characteristics of a compound semiconductor, and LEDs have recently been used as light sources of various electronic products. In particular, the demand for white LEDs is high in the LED field. Typically, a method of combining and using various colored LED chips or a method of using an LED package, in which an LED chip emitting light of a specific color and a phosphor emitting fluorescence of a specific color are combined, has been used to manufacture a white LED.
Recently, instead of using a phosphor, research into methods of manufacturing a white LED using quantum dots, which have better brightness and color reproducibility than the phosphor, has been attempted. However, because the surfaces of currently available quantum dots are generally capped with a hydrophobic ligand for the improvement of dispersibility, the type of dispersible resin is extremely limited. In particular, because a silicon resin or an epoxy resin used as an LED sealing resin has poor affinity to the quantum dots, the quantum dots may not be uniformly distributed but may be agglomerated to reduce a luminous efficiency.
In addition, because quantum dots are easily degraded by the external environment such as heat or moisture, the quantum dots may be degraded by heat generated from an LED chip. Thus, the characteristics of an LED vary depending on the driving time.